As far as I know, you want to find a primer, spraypaint and clearcoat that are flexible. Or, at least have the clearcoat be flexible. The main problem as far as I know is dealing with the flexing, since you can't really prevent paint chipping on the edges when they collide, or if the paint gets scratched. If anything, you'll want to do the best possible prep (sanding/cleaning) to try and keep it strong. I don't know how paints like Krylon Fusion would adhere to a snowboard's topsheet, but any recommendations I've heard were for automotive grade paint.
Vinyl or other adhesive decals are usually suggested since they are more durable and easier to apply.